The present invention relates to an apparatus for converting or reconverting of spin flow energy into pressure energy.
In systems which employ centrifugal forces for the separation of materials, a type of flow emerges from the separation housing and enters into the pipe conduits, which has a spin flow component. Such spin flow component may be smaller or larger, depending on the type of system involved. Since the spin energy within the pipe conduit is lost as such, it may, under certain circumstances, be useful to recover the spin energy by means suitable for this purpose. One advantage of such recovery of the spin energy is seen in that the energy requirement of the material separation system may be substantially reduced. Thus, several different solutions for reconverting the spin energy into pressure energy have been made heretofore.
Thus, it is, for example, known to employ so-called spin diffusers. In such diffusers the spin flow is guided into a pipe of increasing cross sectional flow area. In such a pipe diffuser, the circumferential component, as well as the meridional component of the flow velocity is decelerated due to the increasing flow cross sectional area, whereby pressure energy may be recovered. However, the spin diffuser has the drawback that its flow guide characteristics are disadvantageous. Besides, the flow at the outlet port of such a spin diffuser still comprises a remainder spin. Thus, this type of diffuser is not capable to provide an immediate transition of a spin flow into a parallel flow in a pipe.
Another way of recovering the spin energy employs a spirally shaped housing. Such spin housing is substantially flat and the spin flow enters centrally into the spiral housing in a direction extending perpendicularly to the plane of the spiral and centrally thereof. The flow emerges from the spiral housing from a tangentially extending exit port. One drawback of such housings is seen in that the flow on its way from the center of the spiral to the outer wall of the spiral, is guided in a disadvantageous manner. Such disadvantageous flow or flow guide conditions cause flow losses which substantially diminish the converting efficiency of the housing. It is also disadvantageous from a construction or manufacturing point of view that the inlet channel and the outlet channel form a right angle relative to each other.
Another prior art method for recovering of spin energy employs a so-called axial guide apparatus, wherein the rotating flow in the pipe or conduit is converted or transformed into an annular flow by means of a central body. The annular or ring flow in turn is deflected into the longitudinal direction by means of guide veins arranged in ring fashion. In this manner it is possible to substantially diminish the circumferential component of the ring flow so that at the end of the central body an adequately parallel pipe flow prevails. However, this type of prior art apparatus operates with substantial losses at higher circumferential speeds because the transformation of the spin energy into pressure energy takes place in this type of apparatus along a very short flow passage. In addition, it is necessary to carefully adapt the guide vanes relative to any given operational condition due to the short length of the transformation passage. Thus, where deviations occur from the given operational condition, the apparatus operates with substantial flow losses.